1. Field of the Invention
The present invention relates to a machine tool provided with a protection cover, and particularly to a machine tool provided with a protection cover having a configuration suitable for smooth movement of the protection cover according to a machine movement.
2. Description of the Related Art
In a machine tool, for the purpose of preventing chips generated during machining from piling up on a drive parts of a table, a saddle, or a column, or for the purpose of preventing coolant used in machining from spattering over a drive parts of a table, a saddle, or a column, a telescopic cover is commonly used which expands and contracts in accordance with a movement of a feeding shaft so as to cover these parts (Refer to for example Japanese Patent Laid-Open No. 2001-246531).
A machine tool with a conventional telescopic cover is explained with FIGS. 3A and 3B. FIG. 3A is a top view of the machine tool with the telescopic cover, and FIG. 3B is a front view of the same.
On the bed 1, a table 3 for holding a workpiece 7 is placed through a saddle 2. A column 4 is mounted to the rear side of the bed 1 to support a main spindle 5. A tool 6 is attached to the head of the main spindle 5. A splash guard is provided around the bed 1 to cover the whole machining tool.
A feed mechanism, not shown in FIGS. 3A, 3B is provided between the saddle 2 and the table 3. The table is configured to move in directions of arrows shown in the FIGS. 3A, 3B, by driving the feed mechanism. Telescopic covers 9, 10, 11, and 12, are provided on front side, rear side, and right and left sides of the table 3, in order to protect, for example, the top side of the saddle 2 and the feed mechanism disposed to chips and coolant etc. as the table 3 is moved.
In the machining tool provided with the telescopic cover, explained with FIGS. 3A, 3B, components covered by telescopic covers are protected from chips accumulation and coolant scattering. However, there has been such a problem that, smooth movement of the telescopic covers are prevented by accumulation of cutting chips or wastes on the telescopic covers, by the friction of the cover itself, or by the abrasion or deformation of the cover itself, causing damage of the telescopic covers or deterioration of machining accuracy.